[syzbot] KMSAN: uninit-value in btrfs_leaf_free_space

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    4ebaab5f kmsan: drop unneeded references to kmsan_context_..
git tree:       https://github.com/google/kmsan.git master
console output: https://syzkaller.appspot.com/x/log.txt?x=13f42e41d00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=647ca0f5bbe7703a
dashboard link: https://syzkaller.appspot.com/bug?extid=95a1bcd6d49a5c48b8aa
compiler:       Debian clang version 11.0.1-2
userspace arch: i386

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+95a1bcd6d49a5c48b8aa@xxxxxxxxxxxxxxxxxxxxxxxxx

 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:210
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
=====================================================
=====================================================
BUG: KMSAN: uninit-value in btrfs_leaf_free_space+0x246/0x3d0 fs/btrfs/ctree.c:3533
CPU: 1 PID: 9842 Comm: syz-executor.3 Tainted: G    B             5.12.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x24c/0x2e0 lib/dump_stack.c:120
 kmsan_report+0xfb/0x1e0 mm/kmsan/kmsan_report.c:118
 __msan_warning+0x5c/0xa0 mm/kmsan/kmsan_instr.c:197
 btrfs_leaf_free_space+0x246/0x3d0 fs/btrfs/ctree.c:3533
 setup_items_for_insert+0x180e/0x1a00 fs/btrfs/ctree.c:4765
 btrfs_insert_empty_items+0x6f9/0x790 fs/btrfs/ctree.c:4800
 btrfs_insert_empty_item fs/btrfs/ctree.h:2867 [inline]
 alloc_reserved_tree_block+0x403/0xef0 fs/btrfs/extent-tree.c:4618
 run_delayed_tree_ref+0x3ea/0xa30 fs/btrfs/extent-tree.c:1678
 run_one_delayed_ref fs/btrfs/extent-tree.c:1707 [inline]
 btrfs_run_delayed_refs_for_head fs/btrfs/extent-tree.c:1961 [inline]
 __btrfs_run_delayed_refs+0xf48/0x2c20 fs/btrfs/extent-tree.c:2026
 btrfs_run_delayed_refs+0x5df/0x910 fs/btrfs/extent-tree.c:2157
 commit_cowonly_roots+0xea1/0x1560 fs/btrfs/transaction.c:1272
 btrfs_commit_transaction+0x212b/0x5640 fs/btrfs/transaction.c:2293
 btrfs_commit_super+0x1b7/0x1f0 fs/btrfs/disk-io.c:4210
 close_ctree+0x4b1/0xf57 fs/btrfs/disk-io.c:4275
 btrfs_put_super+0x53/0x70 fs/btrfs/super.c:325
 generic_shutdown_super+0x2ab/0x650 fs/super.c:464
 kill_anon_super+0x63/0xb0 fs/super.c:1056
 btrfs_kill_super+0x61/0x90 fs/btrfs/super.c:2353
 deactivate_locked_super+0x10d/0x1e0 fs/super.c:335
 deactivate_super+0x1b7/0x1d0 fs/super.c:366
 cleanup_mnt+0x7a0/0x870 fs/namespace.c:1136
 __cleanup_mnt+0x3b/0x50 fs/namespace.c:1143
 task_work_run+0x140/0x280 kernel/task_work.c:140
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:174 [inline]
 exit_to_user_mode_prepare+0x486/0x560 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x35/0x60 kernel/entry/common.c:301
 __do_fast_syscall_32+0x14f/0x180 arch/x86/entry/common.c:145
 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:167
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:210
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
RIP: 0023:0xf7f34549
Code: 03 74 c0 01 10 05 03 74 b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
RSP: 002b:00000000fffc5a1c EFLAGS: 00000292 ORIG_RAX: 0000000000000034
RAX: 0000000000000000 RBX: 00000000fffc5ac0 RCX: 0000000000000002
RDX: 000000000816c000 RSI: 0000000000000000 RDI: 00000000080e9e6a
RBP: 00000000fffc5ac0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:121 [inline]
 kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:289
 kmsan_memcpy_memmove_metadata+0x25e/0x2d0 mm/kmsan/kmsan.c:226
 kmsan_memmove_metadata+0xe/0x10 mm/kmsan/kmsan.c:251
 __msan_memmove+0x46/0x60 mm/kmsan/kmsan_instr.c:92
 copy_pages fs/btrfs/extent_io.c:6521 [inline]
 memmove_extent_buffer+0x7c3/0xd30 fs/btrfs/extent_io.c:6589
 setup_items_for_insert+0x11d8/0x1a00 fs/btrfs/ctree.c:4741
 btrfs_insert_empty_items+0x6f9/0x790 fs/btrfs/ctree.c:4800
 btrfs_insert_empty_item fs/btrfs/ctree.h:2867 [inline]
 alloc_reserved_tree_block+0x403/0xef0 fs/btrfs/extent-tree.c:4618
 run_delayed_tree_ref+0x3ea/0xa30 fs/btrfs/extent-tree.c:1678
 run_one_delayed_ref fs/btrfs/extent-tree.c:1707 [inline]
 btrfs_run_delayed_refs_for_head fs/btrfs/extent-tree.c:1961 [inline]
 __btrfs_run_delayed_refs+0xf48/0x2c20 fs/btrfs/extent-tree.c:2026
 btrfs_run_delayed_refs+0x5df/0x910 fs/btrfs/extent-tree.c:2157
 commit_cowonly_roots+0xea1/0x1560 fs/btrfs/transaction.c:1272
 btrfs_commit_transaction+0x212b/0x5640 fs/btrfs/transaction.c:2293
 btrfs_commit_super+0x1b7/0x1f0 fs/btrfs/disk-io.c:4210
 close_ctree+0x4b1/0xf57 fs/btrfs/disk-io.c:4275
 btrfs_put_super+0x53/0x70 fs/btrfs/super.c:325
 generic_shutdown_super+0x2ab/0x650 fs/super.c:464
 kill_anon_super+0x63/0xb0 fs/super.c:1056
 btrfs_kill_super+0x61/0x90 fs/btrfs/super.c:2353
 deactivate_locked_super+0x10d/0x1e0 fs/super.c:335
 deactivate_super+0x1b7/0x1d0 fs/super.c:366
 cleanup_mnt+0x7a0/0x870 fs/namespace.c:1136
 __cleanup_mnt+0x3b/0x50 fs/namespace.c:1143
 task_work_run+0x140/0x280 kernel/task_work.c:140
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:174 [inline]
 exit_to_user_mode_prepare+0x486/0x560 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x35/0x60 kernel/entry/common.c:301
 __do_fast_syscall_32+0x14f/0x180 arch/x86/entry/common.c:145
 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:167
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:210
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:121 [inline]
 kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:289
 __msan_chain_origin+0x54/0xa0 mm/kmsan/kmsan_instr.c:147
 put_unaligned_le32 include/linux/unaligned/access_ok.h:45 [inline]
 btrfs_set_token_32+0x9a6/0xb40 fs/btrfs/struct-funcs.c:162
 btrfs_set_token_item_offset fs/btrfs/ctree.h:1907 [inline]
 setup_items_for_insert+0x10e9/0x1a00 fs/btrfs/ctree.c:4737
 btrfs_insert_empty_items+0x6f9/0x790 fs/btrfs/ctree.c:4800
 btrfs_insert_empty_item fs/btrfs/ctree.h:2867 [inline]
 alloc_reserved_tree_block+0x403/0xef0 fs/btrfs/extent-tree.c:4618
 run_delayed_tree_ref+0x3ea/0xa30 fs/btrfs/extent-tree.c:1678
 run_one_delayed_ref fs/btrfs/extent-tree.c:1707 [inline]
 btrfs_run_delayed_refs_for_head fs/btrfs/extent-tree.c:1961 [inline]
 __btrfs_run_delayed_refs+0xf48/0x2c20 fs/btrfs/extent-tree.c:2026
 btrfs_run_delayed_refs+0x5df/0x910 fs/btrfs/extent-tree.c:2157
 commit_cowonly_roots+0xea1/0x1560 fs/btrfs/transaction.c:1272
 btrfs_commit_transaction+0x212b/0x5640 fs/btrfs/transaction.c:2293
 btrfs_commit_super+0x1b7/0x1f0 fs/btrfs/disk-io.c:4210
 close_ctree+0x4b1/0xf57 fs/btrfs/disk-io.c:4275
 btrfs_put_super+0x53/0x70 fs/btrfs/super.c:325
 generic_shutdown_super+0x2ab/0x650 fs/super.c:464
 kill_anon_super+0x63/0xb0 fs/super.c:1056
 btrfs_kill_super+0x61/0x90 fs/btrfs/super.c:2353
 deactivate_locked_super+0x10d/0x1e0 fs/super.c:335
 deactivate_super+0x1b7/0x1d0 fs/super.c:366
 cleanup_mnt+0x7a0/0x870 fs/namespace.c:1136
 __cleanup_mnt+0x3b/0x50 fs/namespace.c:1143
 task_work_run+0x140/0x280 kernel/task_work.c:140
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:174 [inline]
 exit_to_user_mode_prepare+0x486/0x560 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x35/0x60 kernel/entry/common.c:301
 cleanup_mnt+0x7a0/0x870 fs/namespace.c:1136
 task_work_run+0x140/0x280 kernel/task_work.c:140
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:174 [inline]
 exit_to_user_mode_prepare+0x486/0x560 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x35/0x60 kernel/entry/common.c:301
 __do_fast_syscall_32+0x14f/0x180 arch/x86/entry/common.c:145
 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:167
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:210
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
=====================================================
=====================================================
BUG: KMSAN: uninit-value in check_setget_bounds fs/btrfs/struct-funcs.c:15 [inline]
BUG: KMSAN: uninit-value in btrfs_set_64+0x4ee/0x6e0 fs/btrfs/struct-funcs.c:163
CPU: 1 PID: 9842 Comm: syz-executor.3 Tainted: G    B             5.12.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x24c/0x2e0 lib/dump_stack.c:120
 kmsan_report+0xfb/0x1e0 mm/kmsan/kmsan_report.c:118
 __msan_warning+0x5c/0xa0 mm/kmsan/kmsan_instr.c:197
 check_setget_bounds fs/btrfs/struct-funcs.c:15 [inline]
 btrfs_set_64+0x4ee/0x6e0 fs/btrfs/struct-funcs.c:163
 btrfs_set_extent_refs fs/btrfs/ctree.h:1794 [inline]
 alloc_reserved_tree_block+0x612/0xef0 fs/btrfs/extent-tree.c:4628
 run_delayed_tree_ref+0x3ea/0xa30 fs/btrfs/extent-tree.c:1678
 run_one_delayed_ref fs/btrfs/extent-tree.c:1707 [inline]
 btrfs_run_delayed_refs_for_head fs/btrfs/extent-tree.c:1961 [inline]
 __btrfs_run_delayed_refs+0xf48/0x2c20 fs/btrfs/extent-tree.c:2026
 btrfs_run_delayed_refs+0x5df/0x910 fs/btrfs/extent-tree.c:2157
 commit_cowonly_roots+0xea1/0x1560 fs/btrfs/transaction.c:1272
 btrfs_commit_transaction+0x212b/0x5640 fs/btrfs/transaction.c:2293
 btrfs_commit_super+0x1b7/0x1f0 fs/btrfs/disk-io.c:4210
 close_ctree+0x4b1/0xf57 fs/btrfs/disk-io.c:4275
 btrfs_put_super+0x53/0x70 fs/btrfs/super.c:325
 generic_shutdown_super+0x2ab/0x650 fs/super.c:464
 kill_anon_super+0x63/0xb0 fs/super.c:1056
 btrfs_kill_super+0x61/0x90 fs/btrfs/super.c:2353
 deactivate_locked_super+0x10d/0x1e0 fs/super.c:335
 deactivate_super+0x1b7/0x1d0 fs/super.c:366
 cleanup_mnt+0x7a0/0x870 fs/namespace.c:1136
 __cleanup_mnt+0x3b/0x50 fs/namespace.c:1143
 task_work_run+0x140/0x280 kernel/task_work.c:140
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:174 [inline]
 exit_to_user_mode_prepare+0x486/0x560 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x35/0x60 kernel/entry/common.c:301
 __do_fast_syscall_32+0x14f/0x180 arch/x86/entry/common.c:145
 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:167
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:210
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
RIP: 0023:0xf7f34549
Code: 03 74 c0 01 10 05 03 74 b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
RSP: 002b:00000000fffc5a1c EFLAGS: 00000292 ORIG_RAX: 0000000000000034
RAX: 0000000000000000 RBX: 00000000fffc5ac0 RCX: 0000000000000002
RDX: 000000000816c000 RSI: 0000000000000000 RDI: 00000000080e9e6a
RBP: 00000000fffc5ac0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:121 [inline]
 kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:289
 __msan_chain_origin+0x54/0xa0 mm/kmsan/kmsan_instr.c:147
 put_unaligned_le32 include/linux/unaligned/access_ok.h:45 [inline]
 btrfs_set_token_32+0x9a6/0xb40 fs/btrfs/struct-funcs.c:162
 btrfs_set_token_item_offset fs/btrfs/ctree.h:1907 [inline]
 setup_items_for_insert+0x13e0/0x1a00 fs/btrfs/ctree.c:4758
 btrfs_insert_empty_items+0x6f9/0x790 fs/btrfs/ctree.c:4800
 btrfs_insert_empty_item fs/btrfs/ctree.h:2867 [inline]
 alloc_reserved_tree_block+0x403/0xef0 fs/btrfs/extent-tree.c:4618
 run_delayed_tree_ref+0x3ea/0xa30 fs/btrfs/extent-tree.c:1678
 run_one_delayed_ref fs/btrfs/extent-tree.c:1707 [inline]
 btrfs_run_delayed_refs_for_head fs/btrfs/extent-tree.c:1961 [inline]
 __btrfs_run_delayed_refs+0xf48/0x2c20 fs/btrfs/extent-tree.c:2026
 btrfs_run_delayed_refs+0x5df/0x910 fs/btrfs/extent-tree.c:2157
 commit_cowonly_roots+0xea1/0x1560 fs/btrfs/transaction.c:1272
 btrfs_commit_transaction+0x212b/0x5640 fs/btrfs/transaction.c:2293
 btrfs_commit_super+0x1b7/0x1f0 fs/btrfs/disk-io.c:4210
 close_ctree+0x4b1/0xf57 fs/btrfs/disk-io.c:4275
 btrfs_put_super+0x53/0x70 fs/btrfs/super.c:325
 generic_shutdown_super+0x2ab/0x650 fs/super.c:464
 kill_anon_super+0x63/0xb0 fs/super.c:1056
 btrfs_kill_super+0x61/0x90 fs/btrfs/super.c:2353
 deactivate_locked_super+0x10d/0x1e0 fs/super.c:335
 deactivate_super+0x1b7/0x1d0 fs/super.c:366
 cleanup_mnt+0x7a0/0x870 fs/namespace.c:1136
 __cleanup_mnt+0x3b/0x50 fs/namespace.c:1143
 task_work_run+0x140/0x280 kernel/task_work.c:140
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:174 [inline]
 exit_to_user_mode_prepare+0x486/0x560 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x35/0x60 kernel/entry/common.c:301
 __do_fast_syscall_32+0x14f/0x180 arch/x86/entry/common.c:145
 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:167
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:210
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:121 [inline]
 kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:289
 kmsan_memcpy_memmove_metadata+0x25e/0x2d0 mm/kmsan/kmsan.c:226
 kmsan_memmove_metadata+0xe/0x10 mm/kmsan/kmsan.c:251
 __msan_memmove+0x46/0x60 mm/kmsan/kmsan_instr.c:92
 copy_pages fs/btrfs/extent_io.c:6521 [inline]
 memmove_extent_buffer+0x7c3/0xd30 fs/btrfs/extent_io.c:6589
 setup_items_for_insert+0x11d8/0x1a00 fs/btrfs/ctree.c:4741
 btrfs_insert_empty_items+0x6f9/0x790 fs/btrfs/ctree.c:4800
 btrfs_insert_empty_item fs/btrfs/ctree.h:2867 [inline]
 alloc_reserved_tree_block+0x403/0xef0 fs/btrfs/extent-tree.c:4618
 run_delayed_tree_ref+0x3ea/0xa30 fs/btrfs/extent-tree.c:1678
 run_one_delayed_ref fs/btrfs/extent-tree.c:1707 [inline]
 btrfs_run_delayed_refs_for_head fs/btrfs/extent-tree.c:1961 [inline]
 __btrfs_run_delayed_refs+0xf48/0x2c20 fs/btrfs/extent-tree.c:2026
 btrfs_run_delayed_refs+0x5df/0x910 fs/btrfs/extent-tree.c:2157
 commit_cowonly_roots+0xea1/0x1560 fs/btrfs/transaction.c:1272
 btrfs_commit_transaction+0x212b/0x5640 fs/btrfs/transaction.c:2293
 btrfs_commit_super+0x1b7/0x1f0 fs/btrfs/disk-io.c:4210
 close_ctree+0x4b1/0xf57 fs/btrfs/disk-io.c:4275
 btrfs_put_super+0x53/0x70 fs/btrfs/super.c:325
 generic_shutdown_super+0x2ab/0x650 fs/super.c:464
 kill_anon_super+0x63/0xb0 fs/super.c:1056
 btrfs_kill_super+0x61/0x90 fs/btrfs/super.c:2353
 deactivate_locked_super+0x10d/0x1e0 fs/super.c:335
 deactivate_super+0x1b7/0x1d0 fs/super.c:366
 cleanup_mnt+0x7a0/0x870 fs/namespace.c:1136
 __cleanup_mnt+0x3b/0x50 fs/namespace.c:1143
 task_work_run+0x140/0x280 kernel/task_work.c:140
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:174 [inline]
 exit_to_user_mode_prepare+0x486/0x560 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x35/0x60 kernel/entry/common.c:301
 __do_fast_syscall_32+0x14f/0x180 arch/x86/entry/common.c:145
 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:167
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:210
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:121 [inline]
 kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:289
 kmsan_memcpy_memmove_metadata+0x25e/0x2d0 mm/kmsan/kmsan.c:226
 kmsan_memmove_metadata+0xe/0x10 mm/kmsan/kmsan.c:251
 __msan_memmove+0x46/0x60 mm/kmsan/kmsan_instr.c:92
 copy_pages fs/btrfs/extent_io.c:6521 [inline]
 memcpy_extent_buffer+0x696/0xbc0 fs/btrfs/extent_io.c:6552
 memmove_extent_buffer+0x260/0xd30 fs/btrfs/extent_io.c:6577
 btrfs_del_items+0x9fe/0x1a50 fs/btrfs/ctree.c:4950
 __btrfs_free_extent+0x29d6/0x4df0 fs/btrfs/extent-tree.c:3200
 run_delayed_tree_ref+0x806/0xa30 fs/btrfs/extent-tree.c:1683
 run_one_delayed_ref fs/btrfs/extent-tree.c:1707 [inline]
 btrfs_run_delayed_refs_for_head fs/btrfs/extent-tree.c:1961 [inline]
 __btrfs_run_delayed_refs+0xf48/0x2c20 fs/btrfs/extent-tree.c:2026
 btrfs_run_delayed_refs+0x5df/0x910 fs/btrfs/extent-tree.c:2157
 commit_cowonly_roots+0xea1/0x1560 fs/btrfs/transaction.c:1272
 btrfs_commit_transaction+0x212b/0x5640 fs/btrfs/transaction.c:2293
 btrfs_commit_super+0x1b7/0x1f0 fs/btrfs/disk-io.c:4210
 close_ctree+0x4b1/0xf57 fs/btrfs/disk-io.c:4275
 btrfs_put_super+0x53/0x70 fs/btrfs/super.c:325
 generic_shutdown_super+0x2ab/0x650 fs/super.c:464
 kill_anon_super+0x63/0xb0 fs/super.c:1056
 btrfs_kill_super+0x61/0x90 fs/btrfs/super.c:2353
 deactivate_locked_super+0x10d/0x1e0 fs/super.c:335
 deactivate_super+0x1b7/0x1d0 fs/super.c:366
 cleanup_mnt+0x7a0/0x870 fs/namespace.c:1136
 __cleanup_mnt+0x3b/0x50 fs/namespace.c:1143
 task_work_run+0x140/0x280 kernel/task_work.c:140
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:174 [inline]
 exit_to_user_mode_prepare+0x486/0x560 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x35/0x60 kernel/entry/common.c:301
 __do_fast_syscall_32+0x14f/0x180 arch/x86/entry/common.c:145
 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:167
 cleanup_mnt+0x7a0/0x870 fs/namespace.c:1136
 __cleanup_mnt+0x3b/0x50 fs/namespace.c:1143
 task_work_run+0x140/0x280 kernel/task_work.c:140
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:174 [inline]
 exit_to_user_mode_prepare+0x486/0x560 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x35/0x60 kernel/entry/common.c:301
 __do_fast_syscall_32+0x14f/0x180 arch/x86/entry/common.c:145
 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:167
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:210
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:121 [inline]
 kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:289
 kmsan_memcpy_memmove_metadata+0x25e/0x2d0 mm/kmsan/kmsan.c:226
 kmsan_memmove_metadata+0xe/0x10 mm/kmsan/kmsan.c:251
 __msan_memmove+0x46/0x60 mm/kmsan/kmsan_instr.c:92
 copy_pages fs/btrfs/extent_io.c:6521 [inline]
 memcpy_extent_buffer+0x696/0xbc0 fs/btrfs/extent_io.c:6552
 memmove_extent_buffer+0x260/0xd30 fs/btrfs/extent_io.c:6577
 btrfs_del_items+0x9fe/0x1a50 fs/btrfs/ctree.c:4950
 __btrfs_free_extent+0x29d6/0x4df0 fs/btrfs/extent-tree.c:3200
 run_delayed_tree_ref+0x806/0xa30 fs/btrfs/extent-tree.c:1683
 run_one_delayed_ref fs/btrfs/extent-tree.c:1707 [inline]
 btrfs_run_delayed_refs_for_head fs/btrfs/extent-tree.c:1961 [inline]
 __btrfs_run_delayed_refs+0xf48/0x2c20 fs/btrfs/extent-tree.c:2026
 btrfs_run_delayed_refs+0x5df/0x910 fs/btrfs/extent-tree.c:2157
 commit_cowonly_roots+0xea1/0x1560 fs/btrfs/transaction.c:1272
 btrfs_commit_transaction+0x212b/0x5640 fs/btrfs/transaction.c:2293
 btrfs_commit_super+0x1b7/0x1f0 fs/btrfs/disk-io.c:4210
 close_ctree+0x4b1/0xf57 fs/btrfs/disk-io.c:4275
 btrfs_put_super+0x53/0x70 fs/btrfs/super.c:325
 generic_shutdown_super+0x2ab/0x650 fs/super.c:464
 kill_anon_super+0x63/0xb0 fs/super.c:1056
 btrfs_kill_super+0x61/0x90 fs/btrfs/super.c:2353
 deactivate_locked_super+0x10d/0x1e0 fs/super.c:335
 deactivate_super+0x1b7/0x1d0 fs/super.c:366
 cleanup_mnt+0x7a0/0x870 fs/namespace.c:1136
 __cleanup_mnt+0x3b/0x50 fs/namespace.c:1143
 task_work_run+0x140/0x280 kernel/task_work.c:140
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:174 [inline]
 exit_to_user_mode_prepare+0x486/0x560 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x35/0x60 kernel/entry/common.c:301
 __do_fast_syscall_32+0x14f/0x180 arch/x86/entry/common.c:145
 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:167
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:210
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:121 [inline]
 kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:289
 __msan_chain_origin+0x54/0xa0 mm/kmsan/kmsan_instr.c:147
 put_unaligned_le32 include/linux/unaligned/access_ok.h:45 [inline]
 btrfs_set_token_32+0x9a6/0xb40 fs/btrfs/struct-funcs.c:162
 btrfs_set_token_item_offset fs/btrfs/ctree.h:1907 [inline]
 btrfs_del_items+0x922/0x1a50 fs/btrfs/ctree.c:4947
 __btrfs_free_extent+0x29d6/0x4df0 fs/btrfs/extent-tree.c:3200
 run_delayed_tree_ref+0x806/0xa30 fs/btrfs/extent-tree.c:1683
 run_one_delayed_ref fs/btrfs/extent-tree.c:1707 [inline]
 btrfs_run_delayed_refs_for_head fs/btrfs/extent-tree.c:1961 [inline]
 __btrfs_run_delayed_refs+0xf48/0x2c20 fs/btrfs/extent-tree.c:2026
 btrfs_run_delayed_refs+0x5df/0x910 fs/btrfs/extent-tree.c:2157
 commit_cowonly_roots+0xea1/0x1560 fs/btrfs/transaction.c:1272
 btrfs_commit_transaction+0x212b/0x5640 fs/btrfs/transaction.c:2293
 btrfs_commit_super+0x1b7/0x1f0 fs/btrfs/disk-io.c:4210
 close_ctree+0x4b1/0xf57 fs/btrfs/disk-io.c:4275
 btrfs_put_super+0x53/0x70 fs/btrfs/super.c:325
 generic_shutdown_super+0x2ab/0x650 fs/super.c:464
 kill_anon_super+0x63/0xb0 fs/super.c:1056
 btrfs_kill_super+0x61/0x90 fs/btrfs/super.c:2353
 deactivate_locked_super+0x10d/0x1e0 fs/super.c:335
 deactivate_super+0x1b7/0x1d0 fs/super.c:366
 cleanup_mnt+0x7a0/0x870 fs/namespace.c:1136
 __cleanup_mnt+0x3b/0x50 fs/namespace.c:1143
 task_work_run+0x140/0x280 kernel/task_work.c:140
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:174 [inline]
 exit_to_user_mode_prepare+0x486/0x560 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x35/0x60 kernel/entry/common.c:301
 __do_fast_syscall_32+0x14f/0x180 arch/x86/entry/common.c:145
 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:167
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:210
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:121 [inline]
 kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:289
 kmsan_memcpy_memmove_metadata+0x25e/0x2d0 mm/kmsan/kmsan.c:226
 kmsan_memmove_metadata+0xe/0x10 mm/kmsan/kmsan.c:251
 __msan_memmove+0x46/0x60 mm/kmsan/kmsan_instr.c:92
 copy_pages fs/btrfs/extent_io.c:6521 [inline]
 memcpy_extent_buffer+0x696/0xbc0 fs/btrfs/extent_io.c:6552
 memmove_extent_buffer+0x260/0xd30 fs/btrfs/extent_io.c:6577
 btrfs_del_items+0x9fe/0x1a50 fs/btrfs/ctree.c:4950
 __btrfs_free_extent+0x29d6/0x4df0 fs/btrfs/extent-tree.c:3200
 run_delayed_tree_ref+0x806/0xa30 fs/btrfs/extent-tree.c:1683
 run_one_delayed_ref fs/btrfs/extent-tree.c:1707 [inline]
 btrfs_run_delayed_refs_for_head fs/btrfs/extent-tree.c:1961 [inline]
 __btrfs_run_delayed_refs+0xf48/0x2c20 fs/btrfs/extent-tree.c:2026
 btrfs_run_delayed_refs+0x2cc/0x910 fs/btrfs/extent-tree.c:2157
 commit_cowonly_roots+0xea1/0x1560 fs/btrfs/transaction.c:1272
 btrfs_commit_transaction+0x212b/0x5640 fs/btrfs/transaction.c:2293
 btrfs_commit_super+0x1b7/0x1f0 fs/btrfs/disk-io.c:4210
 close_ctree+0x4b1/0xf57 fs/btrfs/disk-io.c:4275
 btrfs_put_super+0x53/0x70 fs/btrfs/super.c:325
 generic_shutdown_super+0x2ab/0x650 fs/super.c:464
 kill_anon_super+0x63/0xb0 fs/super.c:1056
 btrfs_kill_super+0x61/0x90 fs/btrfs/super.c:2353
 deactivate_locked_super+0x10d/0x1e0 fs/super.c:335
 deactivate_super+0x1b7/0x1d0 fs/super.c:366
 cleanup_mnt+0x7a0/0x870 fs/namespace.c:1136
 __cleanup_mnt+0x3b/0x50 fs/namespace.c:1143
 task_work_run+0x140/0x280 kernel/task_work.c:140
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:174 [inline]
 exit_to_user_mode_prepare+0x486/0x560 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x35/0x60 kernel/entry/common.c:301
 __do_fast_syscall_32+0x14f/0x180 arch/x86/entry/common.c:145
 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:167
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:210
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

Uninit was created at:
 kmsan_save_stack_with_flags+0x3c/0x90 mm/kmsan/kmsan.c:121
 kmsan_alloc_page+0xd0/0x1e0 mm/kmsan/kmsan_shadow.c:274
 __alloc_pages_nodemask+0x827/0xf90 mm/page_alloc.c:5044
 alloc_pages_current+0x7b6/0xb60 mm/mempolicy.c:2277
 alloc_pages include/linux/gfp.h:561 [inline]
 __page_cache_alloc mm/filemap.c:978 [inline]
 pagecache_get_page+0x111d/0x2040 mm/filemap.c:1797
 find_or_create_page include/linux/pagemap.h:405 [inline]
 alloc_extent_buffer+0x8f8/0x33d0 fs/btrfs/extent_io.c:5618
 btrfs_find_create_tree_block+0xb6/0xd0 fs/btrfs/disk-io.c:1024
 btrfs_init_new_buffer fs/btrfs/extent-tree.c:4743 [inline]
 btrfs_alloc_tree_block+0x545/0x2140 fs/btrfs/extent-tree.c:4845
 alloc_tree_block_no_bg_flush fs/btrfs/ctree.c:992 [inline]
 __btrfs_cow_block+0xb93/0x2760 fs/btrfs/ctree.c:1048
 btrfs_cow_block+0xa3c/0xc90 fs/btrfs/ctree.c:1495
 btrfs_search_slot+0x1ad5/0x3f20 fs/btrfs/ctree.c:2676
 lookup_inline_extent_backref+0x73a/0x38e0 fs/btrfs/extent-tree.c:829
 lookup_extent_backref fs/btrfs/extent-tree.c:1045 [inline]
 __btrfs_free_extent+0x4e8/0x4df0 fs/btrfs/extent-tree.c:2984
 run_delayed_tree_ref+0x806/0xa30 fs/btrfs/extent-tree.c:1683
 run_one_delayed_ref fs/btrfs/extent-tree.c:1707 [inline]
 btrfs_run_delayed_refs_for_head fs/btrfs/extent-tree.c:1961 [inline]
 __btrfs_run_delayed_refs+0xf48/0x2c20 fs/btrfs/extent-tree.c:2026
 btrfs_run_delayed_refs+0x2cc/0x910 fs/btrfs/extent-tree.c:2157
 commit_cowonly_roots+0xea1/0x1560 fs/btrfs/transaction.c:1272
 btrfs_commit_transaction+0x212b/0x5640 fs/btrfs/transaction.c:2293
 btrfs_commit_super+0x1b7/0x1f0 fs/btrfs/disk-io.c:4210
 close_ctree+0x4b1/0xf57 fs/btrfs/disk-io.c:4275
 btrfs_put_super+0x53/0x70 fs/btrfs/super.c:325
 generic_shutdown_super+0x2ab/0x650 fs/super.c:464
 kill_anon_super+0x63/0xb0 fs/super.c:1056
 btrfs_kill_super+0x61/0x90 fs/btrfs/super.c:2353
 deactivate_locked_super+0x10d/0x1e0 fs/super.c:335
 deactivate_super+0x1b7/0x1d0 fs/super.c:366
 cleanup_mnt+0x7a0/0x870 fs/namespace.c:1136
 __cleanup_mnt+0x3b/0x50 fs/namespace.c:1143
 task_work_run+0x140/0x280 kernel/task_work.c:140
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:174 [inline]
 exit_to_user_mode_prepare+0x486/0x560 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x35/0x60 kernel/entry/common.c:301
 __do_fast_syscall_32+0x14f/0x180 arch/x86/entry/common.c:145
 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:167
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:210
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
=====================================================
=====================================================
BUG: KMSAN: uninit-value in arch_stack_walk+0x36e/0x3c0 arch/x86/kernel/stacktrace.c:27
CPU: 1 PID: 9842 Comm: syz-executor.3 Tainted: G    B             5.12.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x24c/0x2e0 lib/dump_stack.c:120
 kmsan_report+0xfb/0x1e0 mm/kmsan/kmsan_report.c:118
 __msan_warning+0x5c/0xa0 mm/kmsan/kmsan_instr.c:197
 arch_stack_walk+0x36e/0x3c0 arch/x86/kernel/stacktrace.c:27
 stack_trace_save+0x117/0x1a0 kernel/stacktrace.c:121
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:121 [inline]
 kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:289


---
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